Trypanosoma Cruzi

By Marisa Gallo, Sarah Goglin, and Kara Bischoff

Parasites and Pestilence - Human Biology 103

Spring 2004

An Introduction to Trypanosoma Cruzi

Trypanosoma Cruzi is a flagellate that was discovered by Carlos Chagas in 1910 in Brazil in its insect vector, the reduviid or "kissing bug." The parasite has three morphological forms: the trypanosome, epimastigote, and the amastigote. You may also know this parasite as T. cruzi or American Trypanosomiasis, and the associated disease is called Chagas disease. Several clinical characteristics of the disease are the chagoma lesions, usually at the site of infection, and Romana's sign, which is edema of the eyelid. T. cruzi infection stretches from northern Mexico to southern Argentina and 16-18 million people are currently infected. Eradication of this disease will be difficult because there are many animal reservoirs (all of which are mammalian) such as dogs, cats, pigs, mice, and armadillos. Eighty percent of T. cruzi human tramsission occurs when blood-sucking Triatomine bugs ingest trypomastigotes from infected reservoirs or humans. When the insect feeds on a human, it leaves feces on the skin that contain metacyclic trypomastigotes which then enter the wound or penetrate mucosal membranes. T. cruzi is diagnosed by a complement fixation test or xenodiagnosis. Various treatments can include Nifurtimox or Beznidazole and vaccine research is currently being used to investigate techniques using recombinant DNA and plasmids containing genes encoding surface antigens. In addition to treatment and vaccines, public health measures such as the Southern Cone Initiative in South America have prevented and tracked the disease through elimination of the vector and screening blood donors.

Agent (Classification and taxonomy)

Kingdom: Cellular organism
Phylum: Eukaryota
Class: Euglenozoa
Order: Kinetoplastida
Family: Trypanosomatidae
Genus: Trypanosoma
Species: Schizotrypanum



aka T. cruzi

aka Chagas’ disease, which is caused by T. cruzi

aka American Trypanosomiasis

Markell and Voge’s Medical Parasitology, P. 134